Making the connection between sleep and size
In the study, 225 people whose typical night's sleep was 6.5 to 8.5 hours long were divided into two groups for seven to nine days and nights: On the first two nights, both groups were allowed 10 to 12 hours of time in bed. On the next five nights, one group had 10 hours in bed per night while the sleep-restricted group was only allowed to be in bed from 4:00 a.m. until 8:00 a.m. Some of the people in the sleep-restricted group were then given an additional two recovery nights in the lab, during which they had 12 hours in bed each night.
While in the lab, the participants were able to request meals, snacks, and drinks from a varied menu as often as they wanted to. They could not exercise but were able to engage in a variety of sedentary activities.
People eat more when they don't sleep
At the end of the study, researcher noted the following:
The sleep-restricted group gained approximately 2 pounds while the normal sleepers did not gain weight.
Within the sleep-restricted group, men gained more weight than women, and African Americans gained more weight than whites.
While eating patterns were relatively constant in the normal sleepers, the restricted sleepers ate more food and more calories on the days when bedtime was 4:00 a.m.
Almost all of the extra calories were consumed between 10:00 p.m. and 4:00 a.m., and a greater portion of those calories was from fat than during other times of the day.
In people who stayed in the lab for two recovery nights, eating returned to normal after the first night of regular sleep.
Because of the study location, these results do not tell us for sure what happens to people who chronically miss sleep when at home, where food options may be different and metabolic changes over time may affect weight gain. Still, with the additional evidence from observational studies linking chronic sleep deprivation with obesity, the study's authors reasoned, "Chronically sleep-restricted subjects with late bedtimes may be more susceptible to weight gain and obesity due to overall greater caloric intake as well as increased consumption during late-night hours." They also noted that the increase in fat calories consumed during late-night eating may make people who stay up late especially prone to gain weight.
Sleep is important for many aspects of good health, and chronic sleep loss may contribute to problems like heart disease, stroke, diabetes, depression, and obesity. Here are some things to think about if you are trying to control your weight and haven't been getting enough sleep:
- Prioritize sleep. Turn off the television, computer, and cell phone an hour before bedtime. Choose a bedtime that gives you the best chance at eight hours of sleep.
- Limit nighttime eating. Try to eat dinner a few hours before bed and don't eat again until morning. Feeling full at bedtime can make it harder to get good sleep.
- Have a hearty breakfast. Eating breakfast appears to be important for healthy metabolism. Breakfast eaters tend to eat fewer calories overall and weigh less than people who skip breakfast regularly. What's the best breakfast? Research suggests that it includes both protein and carbohydrate, like eggs and toast or whole grain cereal with nuts.
- Use natural sleep aids. If your sleep tends to be poor despite getting to bed on time, consider using herbal sleep remedies such as those with valerian, chamomile, and passionflower, which are known to have calming, soothing properties without the extra drowsiness or dependence that can be a side effect of medicinal sleep aids. The hormone melatonin is another natural option, though it is advisable to use this with a doctor's supervision.